1. Technical Field
The present application relates to a beverage bottling plant for filling bottles with a liquid beverage material having a bottle filling machine with a filling valve for bottling liquids in containers such as bottles, cans and similar vessels.
2. Background Information
A beverage bottling plant for filling bottles with a liquid beverage filling material can possibly comprise a beverage filling machine with a plurality of beverage filling positions, each beverage filling position having a beverage filling device for filling bottles with liquid beverage filling material. The filling devices may have an apparatus designed to introduce a predetermined volume of liquid beverage filling material into the interior of bottles to a substantially predetermined level of liquid beverage filling material. The apparatus designed to introduce a predetermined flow of liquid beverage filling material further comprises an apparatus that is designed to terminate the filling of the beverage bottles upon the liquid beverage filling material reaching the predetermined level in bottles. There may also be provided a conveyer arrangement that is designed to move bottles, for example, from an inspecting machine to the filling machine. Upon filling, a closing station closes the filled bottles. There may further be provided a conveyer arrangement configured to transfer filled bottles from the filling machine to the closing station. Bottles may be labeled in a labeling station, the labeling station having a conveyer arrangement to receive bottles and to output bottles. The closing station and the labeling station may be connected by a corresponding conveyer arrangement.
The present application relates in particular to the bottling of liquids that contain solid matter, such as beverages that contain fruit pulp and similar substances, such as pulp, cells, fibers or other types of solid matter, for example. These beverages can be bottled using open-jet bottling and without pressing the container against the sealing elements of the filling valve, preferably without counter-pressure.
Filling valves with gas cutoffs or gas locks are used primarily for the bottling of carbonated liquids that are to be transferred from a pressure vessel into a bottle that is connected to the filling mechanism. Before the actual filling begins, the pressure between the bottle and the pressure vessel must be equalized so that the liquid can flow into the bottle on account of the geodetic gradient. During this process, the counterpressure gas in the bottle is displaced into the actual gas headspace as it is replaced by the fluid. For this purpose a return gas tube is used which defines the limit of the actual filling process by means of its bottom end surface, as soon as the level of the fluid reaches said end surface.
An exchange of the gas back into the pressure vessel is thereby no longer possible. On such filling mechanisms, however, there is a danger that the quantity of gas above the surface of the liquid will bubble up through the still open liquid channel, thereby causing an after-running of the liquid that is below the valve seat. To remedy this defect, the prior art has taught that the valve seat can be realized in the form of a siphon and that the valve body can be provided with a cutoff cap which is immersed with its lower edge in the sealing fluid. Apart from the resulting slight reduction in output or capacity or efficiency, this realization of the prior art has the disadvantage that both the groove that forms the siphon channel and the cutoff cap ring must be placed very far down. That is because the cutoff cap is constantly being moved with the valve body of the liquid valve in the closing and opening direction. Because a siphon effect is necessary primarily in the open position, the ring must therefore be at least long enough so that in this position it is immersed to a sufficient depth in the sealing liquid. An additional disadvantage of the configuration of the prior art results from the position of the lower cutoff ring, which differs depending on the open position, which causes constantly changing ratios or conditions of the flow cross sections for the liquid being bottled. That in turn results in different fill levels of the bottles being filled. In addition, special constructive measures that could allow a larger flow cross section taking into consideration the surface tension of the individual liquid being bottled, cannot be introduced as a result of the constantly changing position and the resulting change in the boundary layer of the liquid.
In an additional realization of the prior art, holes are provided at the beginning or on the edge of the cutoff cap to increase the flow cross sections for the liquid being bottled. However, if they are to be perform the desired function, these holes must be raised up from the actual siphon area in the vicinity of the bottling channel, so that it is necessary to provide a siphoning area that can be moved in the axial direction (DE-PS 11 62 711).
DE-AS 1 122 394 also discloses a filling valve for the bottling of liquids in which, in the vicinity of the outlet cross section there is also a disc that has opening slots that run radially. A disc of this type significantly reduces the average open flow cross section. In spite of the radial slots, to the extent that these slots are to perform their intended effect, the flow section cannot be significantly increased.
DE-AS 14 32 312 discloses a construction without a sealing cap which forms the gas cutoff with a backpressure mechanism that incorporates an annular gap and is mounted so that it can move vertically under the action of a spring.
DE-PS 27 27 723 also discloses a construction in which the cap is fastened in a stationary manner to the filling mechanism. The unconventional construction also has disadvantages, however, such as the fact that the cap can no longer be mounted or installed with the valve body, for example.
On filling elements in which the liquid is transported to the bottom of the bottle through a small tube, the rising liquid in the bottle closes the opening of the gas channel for the return gas. It is therefore possible to define the fill level in the bottle by the vertical position of this opening of the gas channel.
When the filling element is realized without a filling tube, in which case the liquid exits the filling element without restriction on the bottle, this type of restriction is not present, because the gas in the neck of the bottle is not prevented from escaping from the bottle. Because of the liquid column that is in the filling element, both the gas that escapes the bottle as well as the surrounding air can rise into the gas headspace of the filler. The bottle would therefore be overfilled, as described above.
To prevent this overfilling, it is possible, for example, to place a narrow-mesh wire screen in the flow path of the liquid, for example, which results in an absolutely secure separation between liquid and gas. The gas—on account of the surface tension that exists between the individual wires—cannot bubble up upward through this wire screen.
The installation of such a narrow-mesh wire screen has the disadvantage that only clear liquids can be bottled, because any fruit particles, fibers, pulp, cells and similar solid matter contained in the beverage will quickly clog the surface of the wire screen and thus interfere with the correct operation of the bottling machine.